1. Field of the Invention
The present invention relates generally to an apparatus for automatically generating and adjusting fuzzy reasoning rules and a method therefor, and more particularly, to an apparatus for automatically generating and adjusting fuzzy reasoning rules which is controlled based on a reasoning error and its change, and a method therefor.
2. Description of the Related Art
Recently, as household electric appliances have been equipped with conventional fuzzy reasoning apparatuses, there has been developed an automatic tuning apparatus for automatically and adjusting fuzzy reasoning rules without manually operating it.
As an example of such an automatic tuning method of automatically generating and adjusting fuzzy reasoning rules, there is proposed an iterative fuzzy modeling disclosed in, Hiroyoshi NOMURA etal., "A Self-Tuning Method of Fuzzy Control by Descent Method," Proc. of 4th IFSA Congress, Brussels, pp. 155-158, 1991. This method enables an embodied apparatus to adjust values of parameters in fuzzy reasoning rules, automatically, at a high speed, so that an error between an output determined by the reasoning rules and predetermined output data can be minimized.
However, the above-mentioned self-tuning method determines the number of fuzzy partitions in an input space or the number of fuzzy reasoning rules by trial and error, and adjusts the parameters for a fixed number of rules. Therefore, it is necessary to repeatedly perform an experiment many times so as to obtain a better result. Further, if the method has determined the parameters using earlier data and tries to further adjust the reasoning rules using currently obtained data, it damages the earlier tuning results or the earlier reasoning rules since the number of rules is fixed, resulting in not obtaining a better result.